Once thought to be a future star of the U.S. national team, Adu, 25, has been going through a period of immense struggles lately. He has been without a club since last November, when he was released by Brazilian Serie A club Bahia.

Since then he has had training stints with English Championship side Blackpool as well as Norwegian club Stabaek, which is currently coached by Adu's one-time international manager, Bob Bradley. Neither club opted to sign Adu, however.

After impressing for the U.S. U-17 national team, the Ghanaian-born Adu began his professional career in 2004, when he signed with MLS side D.C. United as a 14-year-old. After spending three seasons with the Black-and-Red, Adu was traded to Real Salt Lake, where he was reunited with former U.S. U-17 manager John Ellinger. Adu spent just half a season in Utah as he was sold to Portuguese side Benfica in the summer of 2007 for a reported fee of $2 million.

It was at this point where Adu's career turned into an odyssey. Over the next four years, he was loaned out to four different clubs. He experienced a brief revival with Turkish second division side Caykur Rizespor, which resulted in a recall to the U.S. national team. Adu showed well at the 2011 Gold Cup, and had a hand in both U.S. goals during the 4-2 defeat to Mexico in the Gold Cup final.

Adu returned to MLS in August of 2011, where he was reunited with former D.C. United head coach Peter Nowak, but lasted just one-and-a-half seasons before departing for Brazil.

If Adu signs a contract with AZ, he would be the third U.S. international to join in the past four years as Jozy Altidore played with the club between 2011-13 and Aron Johannsson currently plays for the Cheese Farmers, joining the team in 2013. Former U.S. international Earnie Stewart is the club's technical director and is a former teammate of the midfielder with both having played together at D.C. United.